Radioreceiver



Aug. 29, 1933. H. CRAIG 1,924,485

' RADIORECEIVER 1 Filed July 19. 1930 2 Sheets-Sheet 1 Aug. 29, 1933.

IRoN Car h (t UX 112A H. CRAIG 1,924,485

RADIORECEIVER Filed July 19. 1930 2 Sheets-Sheet 2 Patented Aug. 29, 1933 UNITED. STATES A N OFFICE:

I 1,924,485 RADIORECEIVER Hal Craig, Hollywood, Calif. Application July 19, 1930. Serial No. 469,212 7 9 Claimsf (o1. 2I5o 14) This invention relates to a radio receiver and in particular-to a radio receiver constructed for use on an automobile or other vehicles.

,The mounting of radio receivers on automobiles presents numerous problems that demand 210 solution in radio receivers constructed for domestic use. Economy of. room in the domestic receiver may be desirable at times although not essential. In a radio receiver for automobile use it is essential to reduce the space occupied by the radio receiver to a minimum. It is also desimple to eliminate shielding as far as possible consistent with the performance of the device.

' An object of this invention is to arrange the parts with the minimum amount of shielding.

5 This has been accomplished by staggering the transformers of the radio frequency stages with respect to the gang condensers arranged in a row so that the input transformer to a tube is on the opposite side of the gang condensers from that of the output transformer. It'can be readily seen that by so arranging the transformers undesirable coupling is greatly diminished. This is especially the case when the transformers are all arranged in a common plane This permits the close assembly of the radio and audio frequency stages of amplification within the same metallic case without coupling even though the several stages are unshielded.

another object of this invention is to decrease the length of the leads so as to eliminate dis turbances caused by long leads. This has been accomplished by arranging, the gang condenser Another object of this invention is to get a compact assembly. This has been accomplished ,by staggering the radio frequency stages so as to thereby better group theparts, thus reducing the occupied by these.

Further objects and advantages of the present invention will be apparent from. the following description, reference being had to the accompanying drawings, wherein a preferred embodiment of one form of the present inventionis clearly shown. p

a In the drawings:

Fig. 1 discloses a schematic arrangement of the parts of the radio receiver.

same resonant frequency.

are arranged opposite to their respective input arranged in parallel. The details of theielectrical- Fig. 2 discloses a schematicwiring diagram of I the complete radio receiver. i

Fig. 3 discloses a sectional view of the receiver taken on the line 3-3 of Fig. 1. v 1

In the drawings the reference characters 10, l2, l4 and 16 represent the stators of gang condensers provided with the rotors 18, 20, 22 and 24 arranged on a common shaft 25 so that the condensers may be adjusted in unison to the thereby reducing the electromagnetic coupling.

This plane defined by theaxes'of the radio fre- 75 quencytransformers is parallel to the shaft upon which the rotors are mounted and passes through the stators of the condensers so as to' intersect all of the stators into like'sectors as best seenin Fig.3. V #89 The radio frequency amplifying tubes 36, 3 8 and 40 together. with the detector tllb0l=2 have also been staggered with respect to the gang condensers and the shieldBe so that theseft ubes transformer and adjacent to their respective output transformer.- I p The signal from the detector' izisampliiied by means of the audio frequency amplifier that injcludes the audio transformer 44 and thetube 46. The output from thetube .46 is amplified by the tubes 48, and having their. grids 52 and fii, ar-

ranged inparallel and the plates. 56 and 58. also circuit-have not'beendescribedfor the reasonthat' this forms no part of this invention. When this'radio receiver is mounted Within a metallic casing such as either copper or alumiinvention as herein described, constitutes a preferred form; it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

i What is claimed is asfollows:

1. A multi-stage radio receiver including gang condensers arranged in a row, a shield enclosing said gang condensers, and radio frequency transformers of adjacent stages arranged in a staggered relation with respect to and on alternate sides of the shield so as to reduce the undesirable coupling between the transformers thereby reducing undesirable oscillations in the radio receiver. Q 2.- A multi-stage radio receiver including a plurality of gang condensers arranged in a row, a shield for shielding the condensers and'tra'nsformers of adjacent stages arrangedin stepped,

relation on opposite sides of the gang condensers,

vacuum tubes arranged on opposite sides of said condensers and directly opposite said transformers so as to eliminate undesirable coupling between adjacent transformersthereby reducing undesirable noises in the radio receiver.

3. A multi-stage radio receiver including a plurality of gang condensers aligned in a row, a

common shaft for the rotor of said condensers so as to rotate the rotors in unison, and transformers v opposite sides of said gang condensers, and vacuum tubes arranged opposite each transformer so that the gang or tuning condenser is intermediate the input transformer and its tube, an element of the condenser forming part of the electrical connection intermediate the secondary of an input transformer and the grid of the succeeding tube., 7

- 5. A radio receiver including a plurality of gang or tuning condensers aligned ina row, radio frequency transformers placed on opposite sides of said gang condensers in a staggeredrelaticn, thermionic vacuum tubesarranged on opposite sides of the condensers so that the tubes are'arranged in a staggered relation, the primary coil ofthe output transformer having its, winding connected to the plate circuit of a vacuum tube that is adjacent to and on the same side of the gang condensers as said output transformer I 6. In a radio receiver having a plurality of successive stages of radio frequency including a tube,

. a condenser and transformer in each stage,- the 'combination'comprising, a tube and its respective transformeribeing arranged on opposite sides of said condenser, each succeeding stage having its respective tube and transformer arranged on alternate sides of the condenser as related to each adjacent stage, such 'alternate'arrangement of tube and transformer forming a staggered relation of the contributing elements and providing for elimination of undesired coupling between the stages and for the use of short gri d' and plate leads of uniform length.

'7. In a compact radio receivercharacterized by a plurality of stages of radio frequency, in which each stage includes -a tube, condenser and a transformenthe combination comprising, means for grouping and operating the condenser as a gang, said tube and transformer of each stage beingarranged on opposite sides of its respective I transformer,-and the tubes and transformers of each stage alternating respectively with'the tubes each stage, said condensers being aligned in a row, said transformer and tube of each stage being positioned on opposite sides of and closely related to their respective condenser, and transformers andtubes of the successive stages being arranged on alternate sides of the line of condensers to form a stepped relation of both transformers and tubes as respects the condenser line, said transformers being disposed adjacent tube or tubes of adjacentstages and at the base thereof to provide for a closer grouping of the said tubes, said compact arrangement of transformers, con densers and tubesproviding for short leads between the elements of the receiver.

9. A radioreceiver having a compact arrangement of parts, comprising in combination, a plura'litygof stages of radio frequency including a transformer, condenser and a vacuum tube, each transformer and tube being arranged on opposite sides of the condenser in each stage, and veach alternatelyarranged on opposite sides of the condenser line for succeeding stages, each tubebeing positioned opposite to its respective input transformer and adjacent to its respective output transformer, such compact arrangement of transformer, condenserand tube elements providing for the useof short and uniform leads, and the alternate arrangement of the transformers eliminating undesirable coupling between successive stages. I

HAL CRAIG. 

